OK, to answer my own question... I found this on Maemo and installed it, and now streaming FLAC works via Mediastreamer

https://garage.maemo.org/projects/dsp-flac/

The remaining time function in Mediastreamer doesn't work correctly (rather at all), and I can't seek forward in a song, and it is still hanging occasionally, but besides that, the basic streaming of FLAC is working.

So if there is a better solution out there (like Canola2 FLAC/UPNP support in a future version), I'm all ears.

Thanks